package editor

import (
	"testing"

	"glint/internal/theme"

	"github.com/charmbracelet/lipgloss"
)

// spanText concatenates the raw text of a line's spans. It must equal the
// original raw line exactly (markup-visible invariant).
func spanText(spans []Span) string {
	s := ""
	for _, sp := range spans {
		s += sp.Text
	}
	return s
}

func TestRenderSpansPreservesText(t *testing.T) {
	spans := []Span{
		{Text: "ab", Style: lipgloss.NewStyle()},
		{Text: "cd", Style: lipgloss.NewStyle()},
	}
	// rendering may add ANSI, but stripped content is checked elsewhere;
	// here we only assert it does not panic and is non-empty.
	if renderSpans(spans) == "" {
		t.Error("renderSpans returned empty for non-empty spans")
	}
}

func TestScanPlainTextGetsExplicitForeground(t *testing.T) {
	th := theme.FlexokiDark()
	out := ScanLines([]string{"hello world"}, th)
	if len(out) != 1 || len(out[0]) == 0 {
		t.Fatalf("expected spans for one line, got %v", out)
	}
	for _, sp := range out[0] {
		// A style with no foreground returns "" from GetForeground().
		if sp.Style.GetForeground() == lipgloss.Color("") {
			t.Errorf("plain span %q has no explicit foreground", sp.Text)
		}
	}
}

func TestScanPreservesRawTextAcrossConstructs(t *testing.T) {
	th := theme.FlexokiDark()
	lines := []string{
		"# Heading",
		"plain **bold** and *italic* and `code`",
		"- a list item with a [link](http://x) and [[wikilink]]",
		"> a quote",
		"```",
		"raw **not bold** here",
		"```",
		"---",
	}
	out := ScanLines(lines, th)
	for i, raw := range lines {
		if got := spanText(out[i]); got != raw {
			t.Errorf("line %d: span text %q != raw %q", i, got, raw)
		}
	}
}

func TestScanFencedCodeSuppressesInline(t *testing.T) {
	th := theme.FlexokiDark()
	lines := []string{"```", "**x**", "```"}
	out := ScanLines(lines, th)
	// The fence body line should be a single code-colored span, not split
	// into bold spans.
	if len(out[1]) != 1 {
		t.Errorf("fenced line split into %d spans, want 1", len(out[1]))
	}
	if out[1][0].Style.GetForeground() != th.Code {
		t.Errorf("fenced body not code-colored")
	}
}

func TestScanLeadingFrontmatter(t *testing.T) {
	th := theme.FlexokiDark()
	lines := []string{"---", "title: x", "---", "body"}
	out := ScanLines(lines, th)
	if out[0][0].Style.GetForeground() != th.Muted {
		t.Errorf("opening --- not muted")
	}
	if out[1][0].Style.GetForeground() != th.Accent {
		t.Errorf("frontmatter key not accent-colored")
	}
	if out[3][0].Style.GetForeground() != th.Text {
		t.Errorf("post-frontmatter line should be plain text")
	}
}

func TestScanEmptyLineYieldsNoSpans(t *testing.T) {
	out := ScanLines([]string{""}, theme.FlexokiDark())
	if len(out[0]) != 0 {
		t.Errorf("empty line should yield no spans, got %d", len(out[0]))
	}
}

func TestScanHeadingKeepsHashes(t *testing.T) {
	th := theme.FlexokiDark()
	out := ScanLines([]string{"### Title"}, th)
	if spanText(out[0]) != "### Title" {
		t.Errorf("heading hashes dropped: %q", spanText(out[0]))
	}
	if out[0][0].Style.GetForeground() != th.Heading {
		t.Errorf("heading not heading-colored")
	}
}

func TestScanListMarkerThenInline(t *testing.T) {
	th := theme.FlexokiDark()
	out := ScanLines([]string{"- **x**"}, th)
	if out[0][0].Style.GetForeground() != th.ListMarker {
		t.Errorf("first span should be the list marker, got fg %v", out[0][0].Style.GetForeground())
	}
	if spanText(out[0]) != "- **x**" {
		t.Errorf("list line text altered: %q", spanText(out[0]))
	}
}

func TestScanFrontmatterHighlightsKeysAndValues(t *testing.T) {
	th := theme.FlexokiDark()
	lines := []string{"---", "title: Hello", "tags:", "  - one", "  - two", "# a comment", "---", "body"}
	out := ScanLines(lines, th)

	// Char-for-char preservation across every frontmatter line.
	for i, raw := range lines {
		if got := spanText(out[i]); got != raw {
			t.Errorf("line %d: span text %q != raw %q", i, got, raw)
		}
	}
	// Opening and closing --- are muted.
	if out[0][0].Style.GetForeground() != th.Muted {
		t.Errorf("opening --- not muted")
	}
	if out[6][0].Style.GetForeground() != th.Muted {
		t.Errorf("closing --- not muted")
	}
	// "title:" key portion is Accent; the value is Text.
	if out[1][0].Style.GetForeground() != th.Accent {
		t.Errorf("key not Accent-colored, got %v", out[1][0].Style.GetForeground())
	}
	if last := out[1][len(out[1])-1]; last.Style.GetForeground() != th.Text {
		t.Errorf("value not Text-colored, got %v", last.Style.GetForeground())
	}
	// List item marker "-" is ListMarker-colored.
	foundMarker := false
	for _, sp := range out[3] {
		if sp.Style.GetForeground() == th.ListMarker {
			foundMarker = true
		}
	}
	if !foundMarker {
		t.Errorf("list item dash not ListMarker-colored")
	}
	// Comment line is muted.
	if out[5][0].Style.GetForeground() != th.Muted {
		t.Errorf("comment not muted")
	}
	// After the closing ---, normal text resumes.
	if out[7][0].Style.GetForeground() != th.Text {
		t.Errorf("post-frontmatter line should be plain text")
	}
}